Materials, such as ores, chemical substances, ceramic raw materials, magnetic coatings and paints, can be milled using a dry milling or wet milling process.
In general, dry milling cannot break apart a product to save its parts for other uses. Wet milling may be a more intensive process, but it can reduce a product into more components, and into finer particles in the micron & submicron (or nanometer) particle size range, allowing for the production of a greater variety of byproducts and improved physical properties. For example, when organic pigments are reduced to sub-micron sizes, their color is stronger. This allows the customer to use less pigment in an ink, paint, or dye, thereby reducing production costs.
Wet milling, also called wet media milling, is a process in which particles are dispersed in a liquid by shearing, by impact or crushing, or by attrition.
A mill is charged with media (small beads or spheres) and activated by a high-speed agitator shaft to separate the individual particles. When the agitator rotates, it transmits kinetic energy to the media. When the material is pumped through the mill, this energy acts on the solids suspended in a liquid (slurry) to tear them apart (shearing) or crush them, reducing them in size. The particles are simultaneously dispersed in the liquid which is then ready for use or can be dried and separated for use in other products.
Different materials are used for the grinding media. The beads, or balls, can be made of plastic, glass, ceramics such as aluminum oxide and zirconium oxide, steel, and tungsten carbide. Depending on the material that is being ground and what the end-use will be for the product, different media milling processes can be used, including comminution (reduction to minute particles) and de-agglomeration (separating particles that are clustered together). Factors that influence the ultimate particle size are the size of the grinding media, the time the material spends in the grinding chamber, the number of passes through the mill, and the speed of agitation.
With the right media milling equipment, manufacturers can cost-effectively create uniformly fine particles with limited or no contamination. But custom blending and milling requires specialized equipment and knowledge of intricate engineering processes. Manufacturers may lack the resources for making these products in their own facilities because acquisition of all of the necessary equipment and expertise can be expensive. And no single system can do everything; even simple wet milling and mixing installations can require additional premix equipment, tanks, mixers, pumps, filters, electronics and plumbing.
Custom Milling & Consulting, Inc. (CMC) is a leading supplier of media mills, grinding mills and basket mills, and an innovator of dispersion technology.
We offer durable and efficient processing equipment such as the CMC Supermill Plus™ media mill and the CMC Batch Mill. We also provide industrial toll processing services for the automotive, agricultural, pharmaceutical, ceramics, paper coating, power and electronics, specialty chemical and various other industries.
CMC will put our experience to work to meet your unique milling requirements and achieve your desired product at the maximum yield. We will help you choose the most appropriate wet milling process and/or equipment to achieve your desired results. If you are interested in testing different methods, we can use our in-house toll milling services to help you test our equipment by producing production size batches.
Contact us today at 610-926-0984 for more information.